All physical and chemical changes produced in rocks, at or near the earths surface, by atmospheric agents.

What happens to primary minerals in weathering

Primary materials are broken down into secondary minerals

What are the three primary rocks that are broken down via weathering

Igneous

sedimentary

metamorphic

What is ment by disintegration and decomposition in regards to the three rock types

Disintegration is a physical breakdown of rocks into minerals

Decomposition is the chemical breakdown of rocks into minerals

After disintegraion what are two exapmples of minerals that are very slowly weatherd

Quartz

Muscovite

After disintegration what is an example of two minerals that are Slowly Weathered

Feldspar

Biotite

After disintegration what are three examples of minerals that are easily weatehered

Calcite

Augite

Hornblende

What happens to Quartz and Muscovite after continued disintegration

They become Resistant primary minerals

What happens to Quartz and Muscovite after Alteration (Both phsycail and chemical)

Quartz and Muscovite become Silicate Clays

What happens to feldspar and biotite after Decomposition and Recombination

They will become other Silicate Clays

What happens to Calcite Augite and Hornblende After decompoisiton oxidation and hydration

Oxides of

Fe

Al

What can happen to Calcite, Augite and Hornblende when decmoposed

These can be decomposed into an aqeuous solution

What happens to the three rock types after decomposition

Decomposition leads to the dissolvment of these three into an aqeuous solution

What three alternatives can the three rock types in aqueous solution become

Organic acid solution

Hydrolysis

Solution

What becomes of the three rock types after they become an organic acid solution

They form organic complexes of Al3+ and

Fe3+

What do the three rock types become after hydrolysis

Silicic acid

What happens to the three rock types if they remain in solution

They become soluble materials such as

Ca

Mg

K

Na

Fe

SO4

What are the three types of Phsycial (AKA mechanical) Weatehring or disintegration

Temperature

Abrasion

Plants and Animals

What is ment by abrasion

Abrasion can be caused by the sand paper effect of sediments trapped in either water ice or in the wind which can then act to grind down pre existing rocks

How much affect to plants and animals have on the disintegration of rocks

Plants and Animals have a minimal effect on the breakdown of rocks

Besides physical weathering what other type of weathering is there?

Chemical weathering AKA

Biogeochemical weathering

AKA

Decomposition

What three things enhances the effects of chemical weathering

Geological

Biological

Plant

What is ment by geological chemical weatehring

Water and ocygen acts to decompose rocks

What is ment by biological chemical weathering

Microorganisms can create acids

What is ment by plants chemical weathering

Plant root metabolism which i assume removes and adds CO2 i guess

What is ment by Biogeochemical weathering

Biogeochemical weatehring incorporates all of:

Geological

Biological

Plant

Chemical weathering

Define Hydration in relation to Biogeochemical Weathering

Hydration - intact water molecule binds to a mineral

Define Hydrolysis in biogeochemical weathering

Hydrolysis - Water reacts with a mineral with H+ Replacing a cation

Define Dissolution in regards to biogeochemical weathering

Dissolution - Water dissolves minerals by dissolving ions

Define Carbonation and other acid reactions in regards to biogeochemical weathering

Acids will accelerate the effects of weathering

Define Oxidation and Reduction in relation to Biogeochemical weathering

The loss or gain of electrons in relation to oxygen availability

Do weatehring proccess act alone?

No weathering proccess work together

What does physical weathering do to increase biogeochemical weathering

Physical weathering disintegrates rocks which leads to an increased surface area for biogeochemical weathering to act on.

Give an example of how biogeochemical weathering acts together

Hydrolysis can release Fe, Mn which can then be oxidized or reduced

What cna soil colour say about a soil

Soil colour can give an idea of mineral content, movement of nutrients through soil as well as water content

What is soil colour affected by

Organc matter content

Water content

Presence of Fe Mn

Waht colour of soil would iron oxides produce

Red Brown Grey Blue

What colour of soil would we expect Manganese oxide to be

Black

What colour fo soil would we expect Gluconite to be

Green

What clour of soil would we expect Calcite to be

White

Give an example of a Munsell Colour Chart Number

7.5YR 6/4

Of 7.5YR 6/4 what represents Hue

Hue is the first value or 7.5 YR

Of 7.5 YR 6/4 What represents Value

the Number 6 represents the Value number

Of 7.5YR 6/4 what does the 4 represent

the 4 is the Chroma

What is ment by Hue

Hue is a general colour range, Red, green yellow etc.

Waht range can Value have? What does each extreme of the range represent

Value is measured 0 - 10.

0 = pure Black

10 = Pure White

What range is Chroma

Chroma

0-10

Soil Colour--------

What does a brown to black say about a soils attrbutes

A brown to Black says a high amount of organic material is present

What does a black subsurface horizon represent

A Subsurface horizon of Black indicates a Manganese parent material such as basalt is present

What does bright-light soil colour represent

The Eluvial horizon is present

What does it mean in the environment when the E horizon is showing

A showing E horizon means that an environment in which

precipitation > evapotransperation

meaning a leaching of sequoxides has occured

the E horizon is consisting mainly of Silica

What does a soil colour of yellow to redish suggest

Fe3+ is present in the soil

this occurs in well aerated soils

What does a gray greenish blue soil mean

Gray greenish blue is indicitive of a

Fe2+ presence

What environment does a grey greenish blue soil (Fe2+) occur in?

Poorly drained soils

What does a white to gray soil colour represent

White to grey is the accumulation of salts

What parent material would cause a white to gray soil colour

Marl

Quartz

Name from smallest to largest
Clay Sand Silt

Clay 0.002 mm

silt 0.002 - 0.05 mm

Sand 0.05 - 2 mm

What does a smaller size mean in realtion to chemical reactions

A smaller size of soil means a greater surface area on the soil meaning more pore spaces and water holding capacity along with increased surface area for chemical reactions meaning a greater rate of chemical reaction

What five effects does a greater surface area due to smaller particles of soil have

1. Water as thin films greater surface area meaning greater chem rxns

2. Greater Gas retention

3. Faster rate of plant nutrient release

4. Greater attraction for charged minerals

5. microbe reactions

Remerb what u know about sand silt and clay water hlding nutrient holding attraction to eachother size u already know all these things well enough to fill in his chart